pequeno_riscv

Pequeno (meaning "tiny" in Spanish) aka PQR5 is a 5-staged pipelined in-order RISC-V CPU Core compliant with RV32I ISA.

Overview

• RV32I ISA v2.2 + custom instructions

  Assembler and Instruction Manual: https://github.com/iammituraj/pqr5asm)

  FPGA demo of Pequeno running Hello world program: https://youtu.be/GECyL9U5ZxI

• Single-core, Single-issue, In-order execution

• Classic 5-stage RISC-V pipeline

• Intended for baremetal applications, not OS & interrupt capable.

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    chipmunklogic.com                                                    [[[[[[[ O P E N - S O U R C E _
  

Feature set

CPU Feature Set
ISA	RV32I, user-level v2.2
Instructions	All 37 base instructions + 16 custom instructions
Cores	1
Issue	One instruction per cycle
Pipeline depth	5
	Fetch, Decode, Execution, Memory Access, Writeback
Bus architecture	Harvard, separate instruction/data bus
Branch Prediction	Yes, static
Cache	Not available, but can be integrated externally
OS capable	No, privilege modes are not supported
Interrupt/Exceptions capable	No
Debug support	Yes, limited number of signals for simulation purposes only

FPGA Resource utilization

Synthesis summary
Target	Artix-7, xc7a35tcpg236-1
LUTs	2084
Registers	1564
Targetted clock freq	100 MHz

Important notes

Please go through database_readme.txt for information about the organisation of the repo and how to setup the pqr5 build environment.

Disclaimer

This CPU core is intended for educational purposes only. Users are encouraged to review the accompanying license document (LICENSE) for detailed terms and conditions.

Developer

Mitu Raj, Chipmunk Logic, [email protected]